Air conditioning system



Jan. 16, 1934. s R Ew 1,943,613 I I AIR CONDITIONING SYSTEN Filed Nov. 2, 1951 Patented Jan. 16, 1934 PATENT OFFICE AIR CONDITIONING SYSTEM Samuel R. Lewis, Chicago, 11]., assignor, by mcsne assignments, to Chester F. Hockley, receiver for The Silica Gel Corporation, Baltimore, Md., a corporation of Maryland Application November 2, 1931. Serial No. 572,685

- 15 Claims. (Cl. 257-8) This invention relates to ventilating and air conditioning systems and particularly to such systems for use throughout the year.

It is a general object of the present invention to provide a novel and improved method of and system for ventilating and air conditioning.

An important feature of ,the present invention resides in the provision of means for controlling the temperatures in individual rooms or sections of buildings provided with conditioned air from a single conditioning apparatus.

Another important feature of the invention resides in the provision of mechanism which permits the room thermostats to function both in winier and summer for controlling thetemperature of the air in the respective'rooms.

Still another important feature of the invention residesin the use of airs of two temperatures for mixing in the ratios determined by the room thermostats and in diluting one of these airs with a controllable quantity of dehydrated air.

A further feature of the invention resides in the novel method of stratifying cooled air and dividingthe cooled stream into two portions of different temperatures.

Other and further features and objects of the invention will be more apparent to those skilled in the art upon a consideration of the accompanying drawing and following specification wherein are dsclosed several exemplary embodiments of the invention, with the understanding, however, that such changes and variations may be made therein as fall within the scope of the appended claims without departing from the spirit of the invention.

In said drawing:

Figure 1 is a schematic and diagrammatic representation of apparatus for cooling rooms. in accordance with the present invention, showing certainof the cooling chambers in vertical section;

Figure 2'is a horizontal section of a portion of'the apparatus of Figure 1; and

Figure 3 is a fragmentary view showing a modified type of control for the dehydrated air.

In the cooling of buildings having several sections, floors, rooms, or the like, it is often desirable to be able to individually control the temperatures of these subdivisions and yet supply them all with conditioned air for ventilating from a single conditioning system. This necessity arises from the difference in heat loads in theseveral spaces. For instance, one room may be crowded and on a sunny side of the building while another may be practically vacant and on the shady side ofthe building. Obviously air of the same temperature delivered to both 01' these rooms would not provide the same desired tem.- perature in the two'rooms unless such excess quantities were provided as would be uneconomical. In accordance with the present invention two bodies of air are maintained at temperatures on opposite sides of the desired temperatures for the rooms and individual ducts lead from the rooms to mixing dampers, controlled by the room temperatures, for mixing the proper ratios 01' the two airs to obtain the desired temperatures in the lOOIl'iS.

Referring to the'drawing, there is shown at 10, 10', and 10 rooms or sections in a building which are desired to be ventilated and conditioned independently from a single conditioning system. The type of system for providing the conditioned air is more or less independent of this invention. It may use fresh air entirely, recirculated air entirely. or a combination of the two and therefore the inlet duct 12 to the apparatus is considered to be supplied with air from any 'ofthe sources indicated above, some of which may come from the return 13 shown from the room 10. This air passes under the suction of the fan 15 into the chamber 16, first passing over or through a suitable heater 17 of the surface type, then through water sprays emitted from the nozzles 18. Finally theair passes over or thro h a second heater 19 before enteringthe suction side of the fan 15.

The form of apparatus just described is conventional. For winter use the air may be heated by either or both of the heaters 17, 19 and washed and/or humidified by the sprays from the noz-.

zles 18. Where washing alone is desired for cleaning the air without the addition of humidity the second heater 19 is used because heating by the first heater 17 would expand the air and reduce its relative humidity so that moisture would be taken up from the washing sprays.

' Where moisture addition is desired then the first heater 17 may also be used and maintained at such a temperature as to permit the imparting ditions to lower the humidity sufliciently requires a reduction in temperature to a degree which makes the air uncomfortable for direct introduction into the rooms and some heat must be added by the heater 19, or the air must be allowed to warm up in the ducts or be heated by the admixture of recirculated air therewith in accordance with several well known systems, before it can be delivered for use.

u To adapt the apparatus just described to the present systemthe outlet 21 from the fan leads into the upper chamber 22 of a large casing 23. The inclined wall 24 separates this chamber from the lower chamber 25 and a door 26 therein which may be adjustably opened into the path of the incoming air directs some of the entering air into the lower compartment when desired.

At 27, just beyond the entrance to the upper compartment, is a heat exchanger, preferably of the surface type, which may be selectively provided from the pipe 28 with a cooling medium or from the pipe 29 with a heating medium such as steam, by the operation of the two-way valve 30. The rate of flow of either medium is adiustedby the regulator valve 31 under the control of the dry bulb thermostat 32 in the upper compartment 22;

A second damper or door 33 is provided in the partition 24, on the discharge side of theheat exchanger 27, and can be adjusted as shown to position it to intercept and deliver to the lower chamber a portion of the air passing through the exchanger 27. I

Each individual room or section is provided with an air delivery duct 33*, 33, and 33 and each of these ducts is connected to the upper air chamber as shown at 34 and through a vertical branch pipe 35 to the lower air chamber. In the entrance 34 is a damper 36 and in the duct 35 is a damper 3'7, these two being connected together by the link 38 for operation in such a manner that as one is opened the other is closed to permit adjustable mixing of the air flowing from the two chambers. The mixing dampers may conveniently be operated by a diaphragm or other mechanism 39 under the control oi the dry bulb thermostat 40 in the room, each individual room having its thermostat and set of mixing dampers.

For winter use the air is partially heated, and humidified if desired, before delivery to the fan 15. It is then discharged into both the upper and lower chambers by having the 'door 26 partially open. The lower chamber will then be maintained full of air substantially at the temperature delivered by the fan. -The heating me- .dium is delivered to the heat exchanger 27 so that air is discharged into the upper chamber at a higher temperature. The door 33 is closed. The apparatus to the right of the fan is adjusted to provide a temperature for the air in the lower chamber below that desired in any of the rooms and thermostat 32 is set to adjust the flow of steam to the heat exchanger to provide a temperature in the upper compartment a few degrees above that desired in any of the rooms.

Under the above conditions it will be seen that by properly setting the mixer dampers 36, 3 a mixture of air from the two compartments may be introduced into the pipe 33 at such a temperature that when delivered to the room it will provide in that room the desired temperature. The mixing dampers being under control of the room thermostats permit automatic adjustment of the ratio of the warmer and cooler airs to provide the exact required temperature in the room irrespective of .the heat load.

For summer use two modes of operation are possible. According to the first method the air is partially cooled and some of the moisture removed by the water sprays 18 but not suificiently to lower the temperature too greatly. If it is necessary for moisture removal to reduce the air temperature below the lowest temperature desired, for delivery to the two compartments, the heater 19 may be used to raise this temperature again. The door 26 is closed so that all of the air from the fan 15 enters the upper compartment 22 and passes through the heat exchanger which is now provided with a cooling medium such as cold water, lowering the temperature of the air without, however, precipitating any moisture because of the previous precipitation by the water sprays. The door 33 is now partially open. the exchanger separates itself more or less into a cooler stream which flows downward by gravity and a warmer stream which remains near the top of the compartment. The cooler stream will be deflected by the door 33 and discharged through the opening controlled by it into the lower compartment 25 whereas the warmer stream of air will remain in the upper compartment. 1

In accordance with another method of operation, the sprays from the nozzles 18 may be used only for washing the air and all of the cooling imparted to it by the heat exchanger 2'7, in which case the exchanger will probably have to be enlarged above the size required for heating purposes for winter use, or it can be augmented by additional sections to be used for cooling only.

In accordance with either mode of summer operation it will be seen that there are provided, as under winter conditions, two bodies of air, that in the upper chamber at a temperature above that desired in the rooms and that in the lower chamber below that desired in the rooms and these two bodies of air can be mixed 120 by means of the mixing dampers under the control of the room thermostats to provide just the desired temperature in any room.

To provide for more adequate dehydration of the air than is possible with the cold water 125 sprays, without the expenditure of too much energy for reheating, and to permit of better room temperature control, there is provided at 50 a dehydrating plant which may be of the type which removes moisture from the air on its pas- 13( sage through suitable absorbents or adsorbents such, for instance, as silica gel or the like.

Atmospheric air, or even recirculated air, if desired, is taken into the dehydration apparatus at 51 and delivered by the fan 52 in a substantially dry state into the duct 53. The apparatus for dehydrating may be of the well known type in which beds of adsorbent material are provided in multiple so that one or more can 14 be used for dehydrating while others are being revivified for further use by heating, such as by the passage of heated air or products of combustion directly through them. If found necessary an after cooler may be introduced into the 14 duct 53 for removing the heat of adsorption.

The duct 53 is connected to a trunk at which extends horizontally through the lower chamber 25 as seen in Figure 1 and is provided with a plurality of nozzles 55 facing toward the out- 15 The air being cooled by 95.

- relying entirely on lets of the chamber and of a type which introduce the air at relatively high velocity to aid in drawing air through the opening, controlled by the door 33, on the injector principle. action causes intimate mingling of the extremely dry air and the air of humidity greater than desired, to produce an air having a desirable relative humidity.

When the two bodies of air from the upper and lower chambers are mingled by the mixing dampers there is provided the air temperature necessary to produce the proper and desired temperature in the rooms in accordance with the room thermostat settings and a relative humidity well within the comfort range without the expenditure of energy for reheating as in accordance with the systems relying solely on cooling below the dew point for the precipitation of excess moisture.

In order to maintain the desired degree of relative humidity in the lower compartment it may be equipped with a humidistat or wet bulb thermostat which controls, in any convenient manner, the damper 61 in the duct 53 to regulate the quantity of dried air introduced.

In accordance with Figure 3 the quantity of dried air introduced may be regulated by having the humidistat 60 control, through the diaphragm 62, the rheostat 63 on the motor 64 which drives the fan 52 to thus adjust the quantity of air delivered.

Still another method is possible for controlling the humidity and that is by reducing the temperature of the activating gases for the absorbent material so that it is less dehydrated and not so effective in removing the moisture from the airpassing through it.

It will be seen that by the addition of the dehydrating apparatus the system is made to function with the same facility in the summer as in the winter. Without this apparatus and the cooling from'the water sprays it will be seen that two bodies of air of difierent temperatures could not be provided and the mixing dampers under the control of the thermostats 40 would be powerless to regulate the temperatures in the various rooms, some of which may be overheated by the crowds, or the like.

In accordance with the above disclosure, it will be seen that the room thermostats are permitted to select air of the respective rooms. If the efiective temperature becomes so low that the occupants of any room feel too cool even whehtaking all air from the upper chamber, the room thermostats may be adjusted to operate at a higher dry bulb temperature or the thermostat in the upper chamber which controls the cooler may be set to a warmer degree. Also the controller in the lower chamber which governs the dry cool air injection may be adjusted to call for a higher relative humidity in chamber 25 which will make the air in the rooms feel less cold because of the lesser degree of evaporation resulting.

If the occupants of any room feel too warm, the room thermostat may be adjusted to operate at a cooler temperature which will move the mixing damper to deliver more air from the lower chamher and less from the upper chamber. tIt will be apparent that there will not be a great difference in temperature between the airs in thetwo chambers since the separation is only that due to gravity but the introduction'of more dry air from the lower chamber will produce a lower relative This injector sun, ,lights,

optimum temperature forv humidity in the room and thus a lower effective temperature.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is: i

1. In an air conditioning system, in-combination, a pair of air chambers, means to deliver air into one of said chambers, means in said chamber-to lower the dry bulb temperature of the air delivered thereto, means discharging the colder portion of said cooled air into the other chamber, means to mix air from the two chambers to produce a desired temperature and delivery means for said mixture to a room to be cooled.

2. Inan air conditioning system, in combination, a pair of superposed air chambers, means to deliver air into the. upper chamber, means extending across the chamber to cool the entering air, a passage from the bottom of the upper chamber to the lower for the discharge of the cooler air, a duct leading to a room to be cooled, and means to mix regulated quantities of air from each of said chambers for discharge into said duct.

3. In an air conditioning system, incombination, a pair of superposed air chambers, means to deliver air into the upper chamber, means extending across the chamber to cool the entering air, a passage from the bottom of the upper chamber to the lower for the discharge of the cooler air. air dehydrating apparatus, means to deliver dehydrated air therefrom into said lower chamber for mixture with the cooled air therein, a duct leading to a room to be cooled. and means to mix regulated quantitiesof air from each of said chambers for discharge into said duct.

4. In an air conditioning system, in combination, a pair of superposed air chambers, means to deliver air into the upper chamber, means extending across the chamber to cool the entering air, a passage from the bottom of the upper chamber to the lower for the discharge of the cooler air, air dehydrating apparatus, means to deliver dehydrated air therefrom into said lower chamber for mixture with the cooled air therein, a duct leading to a room to be cooled, means to mix regulated quantities of air from each of said chambers for discharge into said duct and means to automatically maintain a constant temperature in the upper chamber.

5. In an air conditioning system, in combination, a pair of superposed air chambers, means to deliver air into the upper chamber, means extending .across the chamber to cool the entering air, a passage from the bottom of the upper chamber to the lower for the discharge of the cooler air, air dehydrating apparatus, means to deliver dehydrated air therefrom into said lower chamber for mixture with the cooled air therein, a duct leading to a room to be cooled, means to mix regulated quantities of air from each of said chambers for discharge into said duct and means to automatically maintain a constant humidity in the lower chamber. a

6. In an air conditioning system in accordance with claim 2, the provision of means responsive to the temperature in said room to determine the ratio of airs from the two chambers for delivery'to the said duct.

7. In an air conditioning system, in combination, means to partially dehydrate air by cooling,

a pair of air chambers, means to deliver air from pass colder strata into the other chamber and means to mix air from the two chambersto obtain a desired temperature.

8. In an air conditioning system, in combination, means to change the temperature and humidity of a stream of air, means to' further change the temperature, means to stratify the air and separate the strata into bodies of differ ent temperatures, means to mix a quantity of air from each body to produce a desired intermediate temperature, separate means to dehydrate another stream of air and means to mix a controlled quantity thereof with one of the said bodies of air.

9. In an air conditioning system, in combina- "ion, means to change the temperature and hu-, midity of a stream of air, means to further change the temperature, means to stratifythe air and separate the strata into bodies of different temperatures, means to maintain the temperature of one body constant, means to dilute the other body with dry air, means to maintain the resultant humidity thereof constant and means tomix a quantity of air from each body to produce a desired temperature.

10. The method of conditioning air comprising moving a stream of air, dividing the stream into two parts, maintaining one part at a constant higher temperature than the other, drying another stream of air, mixing it with said sec- 0nd part to maintain a fixed degree of humidity thereof, delivering a mixture of the first part and the diluted second part to a room and adjusting the ratio of mixture in accordance with the room temperature.

11'. The method of conditioning air comprising moving a stream of air, dividing the stream into two parts, maintaining one part at a constant higher temperature than the other, drying another stream of air, mixing it with said second part to maintain a fixed degree of humidity thereof, delivering a mixture of the first part and the diluted second part to a plurality of rooms individually and automatically adjusting the rabio for each room in accordance with the temperature of that room.

12. The method of conditioning air comprising partially drying and cooling an air stream,then

dividing the stream into two parts, maintaining the temperature of one part higher than that of the other, drying another stream of air, diluting the second part with said second stream and combining air from both parts at such a ratio as to produce a desired temperature in a room.

13. In an air conditioning system, in combination, a pair of superposed air chambers, means to deliver air into the upper chamber, means to cool the entering air, said air stratifying by gravity on cooling, a passage from the bottom of the upper chamber to the lower chamber, air dehydrating apparatus, means to, deliver air through said apparatus, injectors for the dehydrated air positioned to draw air into the lower chamber through said passage and means to mix regulated quantities of air from each of said chambers for delivery to a room.

14. In an. air conditioning system, in combination, a pair of superposed air chambers, means to deliver air into the upper chamber, means to cool the entering air, said air stratifying by gravity on cooling, a passage from the bottom of the upper chamber to the lower chamber, air dehy drating apparatus, means to deliver air through said apparatus, injectors for the dehydrated air positioned to draw air into the lower chamber through said passage, means. to mix regulated quantities of air from each of said chambers for delivery to a room and means responsive to the humidity in the lower chamber to regulate the quantity of dehydrated air delivered thereto.

15. In an air conditioning system, in combination, a pair of superposed air chambers, means to deliver air into the upper chamber, means to cool the entering air, said air stratifying by gravity on cooling, a passage from the bottom of the upper chamber to the lower chamber, air dehydrating apparatus, means to deliver air through said apparatus, injectors for the dehydrated air positioned to draw air into the lower chamber through said passage, means ,to mix regulated quantities of air from each of said chambers for delivery to a room and means responsive to the humidity in the lower chamber to regulate the degree of dryness of the dehydrated air delivered thereto.

' SAMUEL R. LEWIS. 

